def ensure_user_is_valid(self):
"""
this method ensures that a valid user has been provided for the Interaction
returns true if valid user is found else returns false
"""
if self.VISITOR_PARAM_KEY in self.request.GET:
visitor_id = self.request.GET[self.VISITOR_PARAM_KEY]
self.user = Visitor.get_by_visitor_id(visitor_id)
if self.user is not None:
return True
self.has_error = True
self.response = Error('Invalid visitor ID provided')
return False
